The present invention relates to telecommunications and networking, and more particularly to an apparatus, system, and related methods for interworking services between public telephone networks, Intelligent Networks, and Internet Protocol (IP) networks.
Telecommunications originated over a century ago using traditional landline based telephony technology. Over time, standards, protocols, and topologies were developed and optimized to provide telephony services. More recently, wireless telephony was developed as an alternative means of telecommunications. Wireless telephony evolved with its own separate and distinct standards, protocols, and topologies optimized for the mobile telephony environment. The SS7 (Signaling System 7) network was developed to provide digital out-of-band signaling channels for both the landline and wireless telephone networks. The modern public telephone network (PTN) leverages SS7 capabilities to establish telephone call connections and provide advanced services, such as 800 or toll free, calling card, Intelligent Network services, Call Back, Calling Name Delivery, Local Number Portability and wireless roaming services. Further, new architectures and interfaces have been developed recently that permit further integration and cooperation between landline and wireless telephony networks. It has been proven advantageous to share resources and provide PTN services more generically, without being concerned whether the telephone terminals involved in the communication are landline or wireless.
Recently, the IP network (including the public Internet) developed in parallel with the converging landline and wireless telephony infrastructures. While the function of the PTN network was primarily to provide end to end connections between telephone service subscribers, IP networks were developed to interconnect and leverage the information and processing capabilities of millions of networked computers. Given the substantially more complex purpose of the IP network, it evolved as a separate network infrastructure with distinct protocols optimized for the functions to be provided.
Over time, the functions provided by the PTN network have become increasingly more sophisticated. Therefore, it is not surprising that cooperation between the IP network and PTN network is desired, and in some instances, required. For example, it would be advantageous to provide services to the PTN network from the vast resources resident on the IP network. In this regard, one early application used the IP network to setup a connection and establish a voice telephone call. The IP telephone call can be originated from any telephone terminal, such as a conventional telephone terminal or an appropriately equipped computer connected to the IP network, and placed to another telephone terminal, such as any other conventional telephone terminal or another appropriately equipped computer connected to the IP network. While this capability is useful, the IP telephone calls are only capable of establishing an end to end connection across the IP network. As such, no other services or applications can cross the IP network and PTN network border, although the need for doing so persists.
The IETF (Internet Engineering Task Force) is an open international community of network designers, operators, vendors, and researchers concerned with the evolution of the Internet architecture and the smooth operation of the Internet. The actual technical work of the IETF is done in its working groups, which are organized by topic into several areas (e.g., routing, transport, security, etc.). Much of the work is handled via email mailing lists and electronic document submissions. Proposals are discussed, evolved, and implemented if advantageous. Proposals have been submitted attempting to converge the capabilities of the IP networks and telecommunication networks. In services interworking for IP telephone calls, one submitted proposal suggests encapsulating the SS7 protocol stack from the link layer to the above layers, including the MTP level 2 and level 3 layers, the SCCP layer, and the TCAP layer. Another proposal suggests encapsulating the SCCP layer and the above layers in the SS7 protocol stack. However, neither proposal properly addresses differences in the addressing and routing functions as implemented in the IP networks and the PTN networks. In addition, neither proposal defines a convergent protocol between these diverse networks. At best, these proposals might ultimately provide transport on the IP network between two PTN networks.
However, in order to effectively converge and leverage these distinct networks, true interworking is required. Interworking is defined as transporting a message between a first network entity executing a software application program in a first network domain and a second network entity executing a software application program in a second network domain. In other words, interworking refers to exchanging messages between software application programs executing in different network domains. The above proposals fail to provide exchanges of PTN messages, such as TCAP (Transaction Capabilities Application Part) messages, between entities in different networking domains, such as the IP network and the PTN network. Accordingly, a TCAP application executing in IP network and a TCAP application executing in a telecommunication network cannot exchange TCAP messages, cannot exchange telephony services, and cannot interwork effectively. As such, a need exists for a fully functional interworking solution between the IP network and the PTN network to preserve the transparency of TCAP messaging in the PTN networks while the TCAP messages are routed to or from IP networks. Were this solution achieved, telephony based services could be provided from the public telephone network, the IP network, or both, as desired. A number of other advantages would also likely emerge from fully functional interworking between the IP network and the public PTN telephone network, as was observed from the convergence of the landline and wireless network infrastructures.
The present invention provides an apparatus, system, and method for interworking services between the IP network and the public telephone network, including the Intelligent Network and wireless networks. As such, the present invention addresses at least some of the above needs while providing some advantages. According to the present invention, conventional TCAP messages from the public telephone network can be exchanged with encapsulated TCAP messages in the IP network. Software application programs executing in network nodes disposed in the IP network and in the public telephone network can thereby cooperatively process information and exchange services therebetween. Existing services can be provided to telephony services subscribers, while new services could be developed by leveraging the processing capability of network nodes in the IP network, according to the present invention.
In one embodiment, the present invention provides an apparatus for selectively interworking a public telephone network and an IP network comprising a first interface, a second interface, and a processor. Since the public telephone network transmits and receives a TCAP message in a first format and the IP network transmits and receives a second type of message in a second format, interworking is required. The first interface is used for communicating with the public telephone network, and is adapted to exchange TCAP messages in the first format with the public telephone network. Analogously, the second interface is used for communicating with the IP network, and is adapted to exchange the second type of messages in the second format with the IP network. The processor is operably connected to at least one of said first interface and said second interface. Further, the processor is adapted for translating the TCAP message received in the first format from the public telephone network, encapsulating the TCAP message in the second format, and forwarding the encapsulated TCAP message to the IP network. In another embodiment, the processor is further adapted to translate an encapsulated TCAP message received from the IP network and forwarding a TCAP message in the first format to the public telephone network.
An embodiment of the present invention further comprises a storage memory operably connected to the processor for maintaining addressing and routing information related to the public telephone network and the IP network. This storage memory may contain a table correlating a plurality of IP network node addresses and a plurality of public telephone network node addresses, such that the processor can remap the address of an incoming message received from one network into a destination address in the other network. In one embodiment, each IP network node address may comprise an IP address and a port number, and each public telephone network node address may comprise a destination point code and a global title or a subsystem number. In a further embodiment, the processor is adapted to provide approximately SCCP addressing and routing to the IP network, and SCCP addressing and routing to the public telephone network.
In yet a further embodiment, the processor is adapted to serve as a signaling endpoint for the public telephone network and adapted to operate as a signaling transit point for the IP network. In addition, the processor may further be adapted to provide signaling transfer point functions and represent a network node in the public telephone network. The processor can be adapted to forward the encapsulated TCAP message to the IP network and represent a network node in the IP network. The processor can translate the TCAP message received from either the public telephone network or the IP network without altering the TCAP characteristics thereof. Other embodiments describe the translation of messages exchanged in the first format with the public telephone network to/from a second format used within the IP network. Encapsulation and decapsulation message formats are also provided.
In one embodiment, the present invention further provides an apparatus for exchanging encapsulated TCAP messages with the IP network comprising a first interface and a processor. The IP network is adapted to transmit and receive a second type of message in a second format. The first interface is used for communicating with the IP network, and is adapted to exchange encapsulated TCAP messages in the second format with the IP network. The processor is operably connected to the first interface, and is adapted to extract a TCAP message from an encapsulated TCAP message in the second format received from the IP network through the first interface. Further, the processor is adapted to encapsulate a TCAP message and forward the encapsulated TCAP message in the second format to the IP network through the first interface. Accordingly, encapsulated TCAP messages in the second format can be exchanged with the IP network. One embodiment provides the processor adapted to execute TCAP software applications, such that telephony services may be provided by exchanging encapsulated TCAP messages with the Internet. The processor may be adapted to execute a STIP software application such that the SCCP primitives can be provided to the TCAP software application.
In an additional embodiment, the apparatus further comprises a translation device having an IP network interface for communicating with the Internet and having a public telephone network interface for communicating with the public telephone network. The translation device is operably connected to the apparatus through the IP network interface, and is connected to the public telephone network. The translation device is adapted for receiving an encapsulated TCAP message from the apparatus through the IP network, and forwarding a representative TCAP message to the public telephone network. Further, the translation device is adapted for receiving a TCAP message from the public telephone network, and forwarding a representative encapsulated TCAP message to the apparatus through the IP network. Accordingly, TCAP messages can be exchanged between the apparatus and the public telephone network through the IP network.
One embodiment of the present invention provides a system for selectively interworking a public telephone network and an IP network, comprising a first network node, a second network node, and at least one interworking apparatus. The interworking apparatus is operably connected to at least one of the first network node and the second network node. Each interworking apparatus further comprises a first interface, a second interface, and a processor. The first interface is used for communicating with the public telephone network, and is adapted to exchange TCAP messages in a first format with the public telephone network. The second interface is used for communicating with the IP network, and is adapted to exchange Internet messages in a second format with the IP network. Further, the processor is operably connected to the first interface and the second interface, and is adapted to extract a TCAP message received in the first format from the public telephone network and to forward an encapsulated TCAP message in the second format to the IP network. In addition, the processor is adapted for translating an encapsulated TCAP message received in the second format from the IP network and forwarding a TCAP message in the first format to the public telephone network.
Various embodiments of the system according to the present invention are provided. In one embodiment of the system, the first network node comprises part of the telephone network and the second network node comprises of part of the IP network.
Further embodiments provide a processor at the first network node and the second network node, such that each processor can execute a TCAP software application program while TCAP messages and encapsulated TCAP messages are exchanged therebetween.
Other embodiments of the system provide interconnected first and second interworking apparatuses, the first network node connected to the first interworking apparatus, and the second network node connected to the second interworking apparatus. In one embodiment, the first network node and second network node are in a first telephone network and second telephone network respectively. The telephone networks are connected by the IP network through the pair of interworking apparatuses. Various telephony services and signaling transport functions may be exchanged between the first public telephone network and the second public telephone network in the system. In addition, two IP networks can be interconnected in a similar manner, except that the pair of interworking apparatuses is interconnected by the public telephone network. Other system configurations provide Internet telephone terminal to public telephone network connections, short message service messaging service, and various other telephony services provided by the system. Various telephony services and signaling transport functions between the first public telephone network and the second public telephone network may be provided by the system.
One embodiment of the present invention provides an apparatus for selectively interworking the public telephone network and the IP network which comprises means for communicating with the public telephone network, means for communicating with the IP network, and means for translating messages. The means for communicating with the public telephone network is adapted to exchange TCAP messages over the SS7 protocol format with the public telephone network, and to exchange TCAP messages over the IP protocol format with the IP network. The means for translating a message is adapted for translating a TCAP message received in the SS7 protocol format from the public telephone network and forwarding an encapsulated TCAP message in the IP protocol format to the IP network.
Another embodiment of the present invention provides a system for selectively interworking the public telephone network and the IP network, comprising a first network node, a second network node, and at least one interworking apparatus. The interworking apparatus is operably connected to at least one of the first network node and the second network node. Each interworking apparatus further comprises means for communicating with the public telephone network, means for communicating with the IP network, and means for translating. The means for communicating with the public telephone network is adapted to exchange TCAP messages over the SS7 protocol format with the public telephone network, and to exchange TCAP messages over the IP protocol format with the IP network. The means for translating is adapted to translate a TCAP message received in the SS7 protocol format from the public telephone network and forwarding an encapsulated TCAP message in the IP protocol format to the IP network. The means for translating is further adapted to translate an encapsulated TCAP message received in the IP protocol format from the IP network, and forwarding a TCAP message in the SS7 protocol format to the public telephone network.
One embodiment of the present invention further provides an apparatus for exchanging encapsulated TCAP messages with the IP network, comprising means for communicating with the IP network, and means for translating. The means for communicating with the IP network is adapted to exchange encapsulated TCAP messages over the IP protocol format with the IP network. The means for translating is adapted to extract a TCAP message from a encapsulated TCAP message received from the IP network, and to encapsulate the TCAP message and forward an encapsulated TCAP message to the IP network, such that the encapsulated TCAP messages can be exchanged with the IP network. The aforementioned apparatuses and systems may be adapted to exchange TCAP messages in an SS7 protocol format with the telephone network and exchange encapsulated TCAP messages in an IP protocol format with the IP network.
A further embodiment of the present invention provides a method for selectively interworking the public telephone network and the IP network, comprising the steps of receiving a TCAP message, extracting the TCAP message, and encapsulating the TCAP message. The step of receiving a TCAP message comprises receiving a TCAP message from the public telephone network in an SS7 protocol format. Next, the method comprises a step of extracting the TCAP message from the SS7 protocol, and thereafter encapsulating the TCAP message in a second format, such that the TCAP message can be forwarded to the IP network to permit interworking therethrough. The method includes other embodiments that describe translating and encapsulating messages in various formats. The method describes the steps of processing messages in various formats, in converting those messages into a different format, such that TCAP messages can be exchanged between network nodes disposed in the IP network and in the public telephone network. As such, the aforementioned apparatuses, systems, and methods provide fully functional interworking between an IP network and a public telephone network by leveraging TCAP messages in compatible formats.